The docomo Kouza Visa Prepaid service works this way: users get a 16-digit card number linked to their account on Docomo’s electric money service, and they can go ahead to shop online at stores that support Visa, with the money being immediately debited from their account.

Instead of going through the traditional application for a credit card, Docomo subscribers can sign up for the service on its website without the need for screening. They can then choose from one of two cards available: the one-time card — valid for 10 days for those who are casual shoppers — or the regular card that is valid for three years and is aimed at those who want to use the service regularly.